Bell's Vireo is a very common bird in mesquite bosques and
along riparian corridors in the Sonoran Desert. Their arrival in early spring
is a sign of warm and then hot weather to come. They flit incessantly from
branch to branch gleaning insects and spiders from foliage, making them hard to
spot. When they sing they often do so from a concealed perch. Thus Bell's Vireo
often goes unseen; instead its presence is heralded by its loud and
distinct song. Bell's Vireos are small, less than
12 cm in length, slightly bigger than our common hummingbirds.
The drab olive-green and pale underside allow them to become nearly invisible
within the dense foliage where they hunt.